Yeah, more like OP took that missing link and made an unfounded conclusion with it, that was the issue. Like I said, an almost reasonable assumption in a vacuum, excluding all external variables, but we don't live in a vacuum, and there have always been issues with the government properly surveying black people and a host of other variables to consider before ever reaching the conclusion OP did.
This could be plausible, but who fathered the extra kids? Whats' your list of missing variables?